The P50 Specialized Population Research Center described in this proposal will perform research designed to achieve a broad understanding of gonads and their two major products, germ cells and steroid hormones. Studies on oocyte maturation will define how progesterone and related hormones modulate phospholipid methylation, calcium release, and cAMP to induce oocyte maturation. The secretion and function of a newly identified set of testicular mitogens, acidic and basic fibroblast growth factors, will be elucidated both in vivo and in vitro. The hormonal control of gene expression in Sertoli cells will be studied by measuring the accumulation and rates of synthesis of androgen-binding protein and its mRNA. The biology of newly identified Sertoli cell proteins will be studied by immunologic assays following isolation and characterization of a variety of new Sertoli cell secretory products. The structure of the genes in the ornithine decarboxylase gene family will be determined and will be related to how the androgen receptor mediates the regulation of ornithine decarboxylase mRNA synthesis in murine kidney. The structure of the beta-glucuronidase gene and its regulatory elements will be defined and their control by androgens elucidated.